Tunable acoustic fluid mixer having easy access to internal working parts



Nov. 12, 1968 5. cs. SIMONETTI 3,410,529

TUNABLE ACOUSTIC FLUID MIXER HAVING EASY ACCESS TO INTERNAL WORKINGPARTS Filed June 12, 1967 2 Sheets-Sheet 1 INVENTOR. 5596/0 G, 57MON7TINov. 12, 1968 s. s. SIMONETTI 3,410,529

TUNABLE ACOUSTIC FLUID MIXER HAVING EASY ACCESS TO INTERNAL WORKINGPARTS 2 Sheets-Sheet 2 Filed June 12, 1967 United States Patent Ofice3,410,529 Patented Nov. 12, 1968 ABSTRACT OF THE DISCLOSURE A fluidmixer of the type including a fluid orifice for forming a jet whichimpinges upon a blade to cause oscillation of the blade and thoroughmixing of the fluid and any substances carried thereby as a result ofcavitation and other effects produced by the vibrating blade, and anadjustable valve downstream of the blade for varying the back pressureupstream thereof; wherein one or more of the blade assembly, the valveassembly, and the jetforming orifice assembly, may be removed from thefluid mixer through respective slots therein, which slots are exposableby the retraction of exterior sleeves so that the fluid mixer need notbe removed from the line to gain such access; also wherein the valveassembly comprises a conical seat member and a conical valve member,with the valve member spring loaded for slight unseating movement underupstream overpressures; also wherein the axial positions of the bladeassembly and of the valve member are individually adjustable byindividual micrometer movements operable to move the aforesaid sleeveswhich are connected respectively to said blade assembly and said valvemember but which are disconnectable therefrom for the aforesaid axialretraction to expose said individual slots for removal of said bladeassembly and valve member; and wherein the two micrometer movementsrespectively controlling the axial position of the blade assembly and ofthe valve member are supplied with indicia and locking so that any axialsetting of the blade assembly and/ or the valve member is preciselyrepeatable and one set is maintainable.

Background of the invention The principle of mixing fluids and fluidcarried substances by the vibration of a blade excited by a jet of thefluid is described in the Cottell US. Reissue Patent 25,324, issued Jan.29, 1963, and also in the Jones US. Patent 3,169,013, issued Feb. 9,1965. In the Cottell US. Patent 3,176,964, issued Apr. 6, 1965, there istaught the adjustment of the axial position of the blade with respect tothe jet-forming orifice, and also the adjustment of the back pressure bymeans of a downstream throttling valve.

In all of these devices, and even in the last-mentioned Cottell patent,there persist a number of disadvantages, although the basic principlesof this class of mixer are very superior. Specifically, differentliquids having different specific gravity and viscosity and other fluidcharacteristics are optimally mixed with different blade to jetformingorifice distances and difiFerent back pressures. Heretofore, changingliquids, or changing the substances carried by a given liquid, hasrequired that the fluid mixer be shut down so that the internal partscould be adjusted, or at best, as in the last-mentioned Cottell device,previous devices have provided only a rough form of external adjustment.Even where external adjustment has been possible, it has not beenreproducible, and when switching between various forms of liquid ispracticed, it has not been possible to reset the previous settingwithout experimentation to again find the optimum settings for thatliquid.

Moreover, in all of the prior art devices the internal working partsrequire inspection and/ or replacement from time to time, especiallywhen abrasive or other deleterious substances are carried in the liquid.Until the present invention, this has required a complete breakdown ofthe mixer to remove the internal parts, necessitating removal from thefluid line in which the mixer is interposed. As will be understood, thisis a processing inconvenience both in terms of the amount of laborrequired and in terms of the inconvenience.

Summary 0 the invention A fluid mixer including a jet-forming orificeassembly, a blade assembly, and a downstream valve assembly, all axiallymounted, wherein the blade assembly and the valve portion of the tuningvalve assembly are mounted through respective lateral slots in the mixercasing to respective internal sleeves carried thereon, and therespective sleeves are movable by separate micrometer movements, so thatadjustment of the axial positions of the blade assembly and the valveportion are precisely and repeatably adjustable and lockable by means ofthe micrometer movements, and also so that disassembly of the respectiveexternal sleeves from the micrometer movements and the respective bladeassembly or valve portion allows axial retraction of the sleeves toexpose the slots through which the blade assembly and valve portion maybe individually removed. In the illustrated embodiment a separate sleeveis provided covering slots through which the jet-forming orificeassembly is removable. With the invention, the proper setting for anypreviously employed fluid can be attained and maintained by adjustingand locking the micrometer movements, and at the same time the internalworking parts can be removed with very little effort and even withoutremoving the mixer from the line in which it is interposed.

In the figures:

FIG. 1 is a perspective view of a presently preferred but merelyillustrative embodiment of the invention;

FIG. 2 is an enlarged end elevation view of the apparatus shown in FIG.1;

FIG. 3 is a section view of the apparatus shown in FIG. 2 taken alongplane 3-3 therein and showing internal details of construction andassembly;

FIG. 4 is an enlarged detail section view of a portion of the apparatusshown in FIG. 3 taken along plane 44 therein; and

FIG. 5 is an enlarged detail section view of a portion of the apparatusshown in FIG. 3 and taken along plane 55 therein.

Referring now to the figures, there is shown an illustrative embodimentof an improved form of fluid mixer indicated generally at 10, operatingupon acoustic principles (i.e., the liquid whistle type), havingadjustable controls able to tune the mixing for maximum efficiency, andbeing arranged so that the working internal parts thereof are readilyaccessible even while the mixer remains connected at upstream anddownstream ends thereof.

Viewed externally, as in FIGS. 1 and 2, the mixer 10 includes a supportbase 11 having a pair of upright support columns 11a, 1111. An elongatedhousing indicated generally at 20 extends from an upstream inlet orificeindicated generally at 20:: to a downstream outlet orifice indicatedgenerally at 20b, and includes an enlarged centrally located mountingand control portion indicated generally at 30. Mounting and controlportion 30 includes a support collar 35 having connected upper and lowerhalves 35a, 35b mounted for slidable engagement upon support columns11a, 11b, a micrometer adjustment means indicated generally at 40 (FIG.2) nearer outlet orifice b, and a micrometer adjustment means indicatedgenerally at 50 nearer inlet orifice 20a (FIG. 1).

It is a feature of the invention associated with the housingconfiguration, as distinct from the internal working parts, that theentire elongated housing 20 can be raised and lowered upon supportcolumns 11a, 11b in order to make appropriate line connections at inletand outlet orifices 20a, 20b. For that purpose, a pair of flats 11c, 11d(FIG. 2) are provided respectively on columns 11a, 1117. A pair of setscrews a, 30b (FIG. 2) are provided in lower part b of support collar 35so as to bear upon flats 11c, 11d respectively, thereby locking theelongated housing 20 in place vertically upon columns 11a, 11b. A pairof collars 11e, 111 are carried axially on columns 11a, 11b, undermounting and control portion 30, and set screws 11g, 1112 respectivelyare provided therein to bear upon flats 11c, 11d, thereby affordingauxiliary means for locking the elongated housing 20 in place verticallyon columns 11a, 11b. In addition to providing vertical adjustment forpurposes of installation, the support base 11 bears the weight of theentire elongated housing 20 thereby sparing the inlet and outlet fluidlines (not shown) between which the mixer 10 is interposed, from aweight which they may not themselves be capable of supporting. Aplurality of mounting apertures 11i (FIG. 1) are provided for boltingthe support base 11 to its supporting surface, if desired.

As will appear hereinbelow, it is another feature of the inventionassociated with the housing configuration, that a complete removal ofthe internal working parts can be effected without disconnecting theorifices 20a, 20b, from the respective inlet and outlet lines (notshown) to which they are secured. Such removal of internal working partsis desirable periodically for the purpose of cleaning, inspecting, orreplacement thereof, and obviation of the necessity for disconnection ofthe mixer from the fluid lines simplifies the procedure appreciably.

This last feature, and additional features arising from the details ofconstruction, both of the housing and the internal Working parts,including their form, arrangement, and mode of operation, will be bestunderstood by recourse to FIGS. 3-5 inclusive, during the followingdetailed description thereof. The aforesaid additional features will bementioned throughout as sufficient description of their associated partsis set forth.

Referring now to FIGS. 3-5, the elongated housing indicated generally at20 includes an upstream housing portion 21, and a downstream housingportion 22, both being generally tubular in configuration. Connected tothe upstream end of housing portion 21 is an adaptor 26, generallytubular, including inlet orifice 20a, and provided with threads forconnection to an inlet line (not shown). Similarly, connected to thedownstream end of housing portion 22 is an adaptor 27, including outletorifice 20b, for connection to an outlet line (not shown). Usually theadaptors 26, 27 are identical, as illustrated, but they can bedifferent, as the need arises.

Housing portion 21 includes a first annular flange 21a located withinthe mounting and control portion indicated generally at 30, and a secondannular flange 21b, also located within portion 30, spaced from flange21a, and terminating tubular member 21. Correspondingly, housing portion22 has a single annular flange 22a, located terminally thereon withinportion 30. The flanges 21b, 22a respectively of housing portions 21, 22are in axial contact within mounting and control portion 30, somewhatoffset from the center thereof So as to be located closer to micrometeradjustment means rather than 50. A peripherally spaced plurality ofscrews (FIG. 3) axially connect the housing portions 21, 22 at themating flanges 21b, 2211.

Housing portions 21, 22 each include, at their respective ends adjacentflanges 21b, 22a, an annular recess 210, 220, which cooperate when theflanges 21b, 22a are in axial contact, to define a single annularrecess. Closely held within that single annular recess 21c, 220 is atuning valve seat member 23 of generally cylindrical outline and havinga pair of conical bores 23a, 23b, each diminishing in diameter towardthe center of tuning valve seat 23 where they meet, so that seat member23 is symmetrical and can be reversed within the annular recess 21c,220. In the illustrated orientation of seat member 23, the surface ofconical bore 23b, being oriented downstream, is the actual seat surface.A pair of annular grooves 23c, 23d are provided in the outer cylindricalsurface of seat member 23 respectively adjacent the annular recessportions 21c and 220. Within each of annular grooves 23c, 23d is carriedan O-ring 23a for sealing of the respective interfaces between tuningvalve seat member 23 and annular recess portions 21c and 220. As willappear more fully hereinbelow, access to, and removal or replacement of,tuning valve seat member 23 is accomplished by parting the housingportions 21, 22 at their flanges 21b, 22a after removal of screws 60.

Flange 22a of housing portion 22, and flange 21a of housing portion 21,each includes an annular stepped portion 22am, 21aa respectively, ineach instance facing away from the main body portion of the associatedhousing portion, i.e., toward the center of mounting and control portion30. The micrometer adjustment means indicated generally at 40 is mountedfor rotation on flange 22a, and the micrometer adjustment meansindicated generally at 50 is mounted for rotation on flange 21a. Theparts are identical as between means 40 and 50, and detailed descriptionwill be made with respect to means 40.

Micrometer adjustment means 40 includes an annular micrometer thimble41, an annular retaining ring 42, and an annular calibrator ring 46.Thimble 41 is located on the side of flange 22a adjacent the main bodyportion of housing portion 22, and includes a main body portion 41ahaving a surface 41b bearing axially against flange 22a, and a tabportion 410 having a surface 41d bearing radially against flange 22a.Tab portion 410 extends across the top of flange 22a into flushregistration with the surface of stepped portion 22aa. Micrometerretaining ring 42 bears against the aforesaid flush surfaces of steppedportion 22aa and tab portion 410, and is of suflicient thickness sothat, when in place as illustrated, the surface thereof remote frommicrometer thimble 41 lies flush with the interface between flanges 21b,22a. A plurality of screws 42a are countersunk through retaining ring 42and into the tab portion 410 of micrometer thimble 41 in order tocapture thimble 41 axially on flange 22a for rotation thereon. Thesurface 41b of micrometer thimble 41 is provided with an annular grooveand O-ring 41], while the retaining ring 42 is provided with an annulargroove and O-ring 42b, for sealing of the corresponding interfaces.Micrometer thimble 41 is provided with four micrometer handles 41g whichare secured by screw threads into tapped apertures in the main portion41a of the micrometer thimble 41. The radially inward surface 41i of themain body 41a of micrometer thimble 41 is spaced from and parallel tothe housing portion 22 and is provided with screw threads therealong.The orientation of calibration ring 46 to thimble 41 will be describedafter description of a tuning valve sleeve 70, which is engaged with andmoved axially by thimble 41.

Tuning valve sleeve 70 extends from flange 22a along a portion oftubular member 22, and has an inner diameter such as to allow closesliding contact therewith. Unlike the parts of micrometer adjustmentmeans 40 and 50 themselves, sleeve 70 varies somewhat from thecorresponding sleeve (to be described) mated with means 50, althoughthey are very similar. The main portion of tuning valve sleeve 70 is ofa thickness sufficient to provide clearance with the threaded surface411' of micrometer thimble 41, but an L-shaped portion 70:: thereof mostadjacent to flange 22a is of greater thickness, and is threaded, so asto threadedly engage with the threaded surface 411 of micrometer thimble41.

Tuning valve calibrator ring 46 has annular stepped surfaces radiallyand axially mated with micrometer thimble 41, and has an inwardlyextending annular portion 46a which touches the main outer surface oftuning valve sleeve 70. An inclined surface 46b thereof is provided(FIG. 2) with radial index markings 460 which cooperate with markings ontuning valve sleeve 70 to yield micrometer readings in known fashion.While the markings on sleeve 70 cannot be seen in the drawings, they areidentical to those on the other sleeve, to be described below,associated with thimble 50, and visible in FIG. 1. The inwardlyextending portion 46a of calibration ring 46 is provided with an annulargroove and O-ring 46d at the contacting surface with sleeve 70, and thehousing portion 22 is provided with a pair of annular grooves 22d alongthe portion thereof underlying sleeve 70 and having O-rings 22e carriedtherein, for sealing of the respective contacting surfaces.

It will be understood that micrometer thimble 41, being carried forrotation upon flange 22a as aforesaid, can be rotated thereon bymanipulation of handles 41g. Rotation of micrometer thimble 41 causes,within the limits of travel determined by flange 22a and inwardlyextending portion 46a of calibration ring 46, axial movement of tuningvalve sleeve 70 along housing portion 22 by virtue of the threadedengagement therebetween. The sleeve 70 is prevented from rotation withthe micrometer thimble 31 by means presently to be described inconnection with other functions.

As previously mentioned, the parts of micrometer adjustment means 50 areidentical to those already described with reference to micrometeradjustment means 40. Briefly, means 50 includes a micrometer thimble 51mounted for rotation on flange 21a, a micrometer retaining ring 52, anda calibrator ring 56. Screws 52a connect retaining ring 52 to thimble51, and set screws 56f connect calibrator ring 56 to thimble 51, so thatring 52 and ring 56 rotate with thimble 51. Four handles 51g arethreadedly mounted in thimble 51. A blade adjustment sleeve 72 iscarried upon tubular member 21 in the same manner as has already beendescribed with reference to tuning valve sleeve 70, and is threadedlyengaged with micrometer thimble 51 for the same purpose, i.e., axialmovement of sleeve 72 on housing portion 21. Calibrator ring 56 alsoincludes markings 560 (FIG. 1) and, as with means 40, these cooperatewith markings on the associated sleeve to calibrate the adjustmentthereof. These latter markings are shown at 56d in FIG. 1. Thearrangement of O-rings between both the thimble 51 and retaining ring 52with flange 21a, and between both the housing portion 21 and the bladecalibration ring 56, is the same as has already been described withreference to the corresponding parts of micrometer adjustment means 40.The only functional difference between the various parts associated withmicrometer adjustment means 50 and sleeve 72 on the other hand, residesin a shortened axial length of blade adjusting sleeve 72 as compared totuning valve sleeve 70. The purpose and extent of this shortening willbe presently described with reference to internal features of theapparatus.

Housing portion 22 includes a pair of opposed longitudinal slots 22n(FIG. 3). A valve member indicated generally at 80 (FIG. 5) is carriedwithin slots 22m. Valve member 80 comprises a body portion 81 whichextends laterally into slots 22m. A pair of shoulder screws 62 passthrough tuning valve sleeve 70 and are threadedly engaged within valvebody 81 so that valve body 81 is moved axially within tubular member 22with axial movement of tuning valve sleeve 70. A valve stem 82 iscarried within a bore 81a within valve body 81 and is smaller in radiusthereby providing an annular gap therebetween. A head 82a is provided atthe downstream end of valve stem 82,

a stepped shoulder 82b is provided at a centrally located portion, andan annular groove 82c is provided at the upstream end of stem 82. Avalve piston 83 has a conical working surface 83a adapted to mate with(FIGS. 3 and 5) the conical bore 23b of tuning valve seat 23. Valvepiston 83 includes a central bore 83b mated with valve stem 82, and thedownstream extreme of piston 83 abuts shoulder 82b. A set screw 830 isprovided in piston 83 for engagement with annular groove 820 in valvestem 82 to removably mate piston 83 and stem 82. A compression spring 84is carried coaxial with valve stem 82 within the bore 81a of valve body81, with one end thereof bearing against piston 83, and the other endthereof bearing against the remote portion of body 81, thereby bottominghead 82:: against body 81. The maximum height of valve member is nogreater than the height of slots 22m, 22n and the maximum axial lengthof valve member 80 is no greater than the axial length of slots 22m,2211.

As has already been explained, movement of tuning valve sleeve 70 bymicrometer thimble 41 within the axial limits permitted by flange 22aand ring portion 46a, will move valve body 81 therewith within equalaxial limits because of the positive connection therebetween at screws62. The conical working surface 83a of piston 83 is thereby axiallymoved toward and away from the valve seat 23. In FIGS. 3 and 5 thesleeve 70 is shown at one axial extreme of its movement, in axialcontact with flange 22a, corresponding to the closed position of thetuning valve parts 80, 23 as illustrated. When the valve is totallyclosed as illustrated, the entire apparatus 10 is prevented fromdeveloping internal over-pressures upstream of the valve which coulddamage the upstream pumping system, by the check-valve effect inherentin the ability of piston 83 to move in the unseating direction againstspring 84. The spring rate of spring 84 is chosen to be suflicientlygreat so as to provide this check valve feature when the piston 83 is inthe fully closed position, but to permit essentially no piston movementwhen the piston 83 is in any degree of open orientation with respect toseat 23. When the micrometer thimble 41 is turned so that sleeve 70 ismoved, the valve piston 83 is moved correspondingly away from the valveseat 23, thereby proportionately reducing the back pressure developed inthe chamber 120 between the upstream side of valve seat 23 and thedownstream side of jet forming fixture 100. As will presently beexplained, this adjustment of the position of valve piston 83 withrespect to valve seat 23 acts to tune the operation of the apparatus 10by adjusting the pressure in chamber 120.

It is an important feature of the invention that valve member 80 can beremoved for cleaning or replacement or the like without removing theapparatus 10 from upstream and downstream connections in the line inwhich it is interposed. This can be accomplished as follows. The bolts62 are first removed so as to free valve body 81 within slots 22m, 2211.The set screws 46 in tuning valve calibrator ring 46 are next removed,and the ring 46 can then be moved axially completely out of the waytoward the remote end of housing portion 22. This latter step removesthe restraint upon sleeve 70 represented by portion 46a of ring 46, andaccordingly the micrometer thimble 41 can then be turned to advance thesleeve 70 away from flange 22a axially until there is no furtherthreaded engagement, upon which the sleeve 70 can manually be furtherremoved axially out of the way toward the portion of housing portion 22adjacent orifice 20b. This latter step exposes the slots 22m, 22n inhousing portion 22. The valve member 80 can then be moved axially intocongruence with the slots 22m and removed laterally out of either of theslots.

Housing portion 21 includes a pair of opposed longitudinal slots 21m,2111 (FIGS. 3 and 4). A blade assembly indicated generally at (FIG. 3)is carried within slots 21m, 2112 (FIG. 4). Blade assembly 90 comprisesa blade 91 having a knife-edge end 91a, a support end 911) and anintermediate shoulder 91c. A blade holder 92 extends laterally (FIG. 4)into slots 21m, 2111. Blade holder 92 includes a centrally locateddepressed portion in the upper surface thereof indicated at 92:: in FIG.4, extending downwardly slightly more than half the depth of bladeholder 92, and having a lateral width slightly greater than the lateralwidth of blade support portion 91b of blade '91. Blade support portion91b is nested within depressed portion 92a, and a blade block 93overlies blade support portion 91b within depressed portion 92a. Bladeblock 93 covers the entire blade support portion 91b and extendslaterally fully within depressed portion 92a of blade holder 92.

The height of blade support portion 9112 together with the height ofblade block 93 is suflicient to fill in depressed portion 92a of bladeholder 92 completely, so that a uniform height of blade assembly 90 ispresented. As can be seen in FIGS. 3 and 4, this height of bladeassembly '90, which is the maximum height thereof, is such as toconstitute a sliding fit within the height of slots 21m, 2111. Also, thelength of blade assembly 90 from blade edge 91a to the remote portion ofblade assembly 90 is smaller than the length of slots 21m, 2112. A pairof shoulder screws 63 pass through blade adjustment sleeve 72 and arethreadedly engaged within the lateral portions of blade holder 92 sothat the blade assembly 90 is moved axially within housing portion 21with axial movement of blade adjustment sleeve 72. Screws 63 are sealedby O-rings 63a at flats under their heads.

Housing portion 21 also includes a pair of opposed slots 21p, 21q (FIG.4) located upstream of slots 21m, 21n, i.e., further toward orifice 20a.The downstream extreme of slots 21p, 21q is spaced slightly upstreamfrom knife-edge 91a of blade assembly 90 when blade assembly 90 is inthe extreme upstream position shown in FIGS. 3 and 4. Unlike slots 22mand 21m, 21n, which are relatively shallow in height and relatively longaxially, slots 21p, 21q are relatively short axially and relativelygreat in height. Thus, slots 21p, Zlq do not present a longitudinalconfiguration along the opposed sides of housing portion 21, but ratherpresent a partial circumferential configuration in the opposed sides ofhousing portion 21. That is to say, slots 21p, 21q occupy major portionsof the annulus of housing portion 21 thereat, their mutual upperportions being spaced, and their mutual lower portions being spaced, toleave stock remaining at the upper and lower extremes of housing portion21 thereat as may be seen in FIG. 3.

As may be seen in FIG. 4, a lateral shoulder 21p is provided by thehousing portion 21 at the downstream extreme of slot 21p, and acorresponding lateral shoulder 21g is provided by the housing portion 21at the downstream extreme of slot 21q. The bore diameter within housingportion 21 immediately adjacent to slots 21p, 21q on the downstream sidethereof, is slightly less than the height of slots 21p, 21q. Thus, asmay be seen in FIG. 3, shoulder portions are formed between the bore 95and the upper and lower portions 21p" of slot 21p. These shoulderportions of course continue across the upper and lower portions ofhousing portion 21 between slots 21p, 21: and have been designated asshoulders 2111" only for convenience, since they are the mutualcontinuation of both lateral shoulders 21p, 21q, across the upper andlower portions thereof. The lateral shoulders 21p, 21q thus extend, innarrowed form, across the upper and lower portions of housing portion 21at portions 21 2", thereby providing in effect a complete annularshoulder.

A jet forming fixture 100 is carried partially within bore 95 andpartially within slots 21p, 21q as may be best seen in FIG. 3. Withreference to FIG. 4, it will be seen that a downstream portion th: has acylindrical outer configuration which fits closely within bore 95', anda pair of laterally extending tabs 1001; (FIG. 4) which extendrespectively into the downstream portions of slots 21p, 21q. The tabs16Gb have a vertical dimension sufficient so that they fit closelywithin the vertical dimension of slots 21p, 21: and thereby abut upperand lower shoulder portions 21p' (FIG. 3). Jet forming fixture 100 isthereby retained axially upon lateral shoulders 21p, 21q' around theaforesaid complete annular periphery thereof, including at the upper andlower shoulder portions 21p shown in FIG. 3, against fluid pressureexerted from upstream thereof. Fixture 190 is sealed by O-ring 100x. Aretaining ring 110 is carried within slots 21p, 21g, and has a verticaldimension (FIG. 3) equal to the height of slots 21p, 21q and ahorizontal diameter (FIG. 4) equal to the outer diameter of housingportion 21 so that the slots 21p, 21: are fully occupied (these lateralportions of ring 110 are partially broken away in FIG. 4 to show theslots 21p, 21(1). The longitudinal dimension of retaining ring 110 issuflicient to form a close fit longitudinally within slots 21 21q withthe portions 10Gb of jet forming fixture 100.

The internal bore of retaining ring 110 is of the same diameter as theinternal bore of housing member 21 immediately upstream thereof. Jetforming fixture 100 in cludes a chamber 100d having an upstream openingof the same diameter as the internal bore of retaining ring 110, and adownstream lateral slit opening 100e in a domed wall 100i. Slit 1006 isdirectly in line with blade edge 91a of blade assembly 90, so that whenfluid is pumped through orifice 20a and into chamber 100d underpressure, a high pressure fluid jet is formed on the downstream side ofslit opening 100e and impinges directly upon blade edge 91a.

As can clearly be seen in FIGS. 3 and 4, blade adjustment sleeve 72 isshortened, as aforesaid, as compared to tuning valve sleeve 70.Specifically, blade adjustment sleeve 72 is sufliciently short so thatthe upstream end thereof lies axially in the vicinity of jet formingfixture 100 when sleeve 72 has been axially advanced to its upstreamlimit by micrometer thimble 51 (i.e., until it is stopped by calibratorring 56) as is illustrated in FIGS. 3 and 4. The exact position of theupstream end of blade adjustment sleeve 72 when at its upstream extremeis not otherwise critical, except that it should not extend to thelongitudinal position occupied by the downstream extreme of slots 21p,21c for disassembly reasons that will appear presently. A short sleeve28 is carried on housing portion 21 overlying slots 21p, 21q and, whenblade adjustment sleeve 72 is at the limit of its upstream movement, isin abutment therewith. Sleeve 28 has the same inner and outer diameterdimensions as sleeve 72, and is axially secured in position on housingportion 21 by a pair of set screws 28a, 28b.

It will be understood that, in the manner already described withreference to the adjustment of the axial position of valve body bymicrometer adjustment means 40, the axial position of blade assembly 9%)is accomplished by micrometer adjustment means 59. Briefly, movement ofthmble 51 at handles 51g moves sleeve 72 in the axial directions,thereby causing blade edge 91a to move with assembly closer to orfurther from orifice 1002 within the same axial limits as are set uponsleeve 72 itself by ring 56 and flange 2.1a.

It is another important feature of the invention that either or both ofblade assembly 90 and jet forming fixture can be removed for cleaning orreplacement or the like without removing the apparatus 10 from upstreamand downstream connections in the line in which it is interposed. Thiscan be accomplished as follows. The set screws 28a are loosened,allowing sleeve 28 to be moved axially upstream over adaptor 26, thusexposing slots 21p, 21g. If it is desired to remove jet forming fixture180, this is accomplished by first sliding ring out of either of slots21p, 21q, and then moving fixture 100 axially upstream into fullcongruence with slots 21p, 21q, and sliding it out of either of slots21p, 21:

If it is desired to remove only blade assembly 90 and not jet formingfixture 190, the sleeve 28 will be loosened and moved axially upstreamas aforesaid, but the ring 110 and fixture 100 will be left in place. Ifit is desired to remove both jet forming fixture 100 and blade assembly90, the foregoing removal will be practiced first. In either of theseinstances, the next step involves removal of blade assembly 90. This isaccomplished in the same manner as has already been described withreference to valve member 80. Briefly, set screws 56 are loosened,allowing calibrator ring 56 to be moved axially upstream out of the way,thereby removing the upstream stops on the movement of blade adjustmentsleeve 72. The sleeve 72 is then unthreaded from thimble 51, and axiallymoved upstream cut of the way, thus exposing slots 21m, 2111. Bladeassembly W is then moved downstream until fully congruent with slots21m, 2112, and is removed laterally through either of them.

From what has already been said, it will be appreciated that, withoutremoving the mixer from the line in which it is interposed, three of thefour sensitive working internal parts can be removed, i.e., the valvebody 80, the blade assembly 90, and the jet forming fixture 100. Inorder to remove the tuning valve seat member however, removal from thelines must be practiced. Thus, bolts (not shown) are countersunk intobolt holes on either side of the upper edge of upper support collarportion 35a, one of which may be seen at 35c in FIG. 1, to engage theupper and lower portions 35a, 35b. To remove seat member 23, these boltsare first removed, and then the set screws a, 30b and 11g, 1111 areloosened, to move the portion a upwardly and the portion 35b downwardly,thereby eXpOsing the bolts (FIG. 3). Bolts 60 are then removed, so thathousing portions 21, 22 can be moved apart axially to yield the seatmember 23.

In general, the jet forming fixture 100 and the seat member 23 do notfrequently need cleaning, and almost never need replacement becauseneither undergoes any significant wear. However, the blade assembly 90,and especially the valve member 80 with its internal parts, can requirefrequent cleaning or replacement, especially when hostile fluids arecarried by mixer 14 In addition to the ease of access to the sensitiveinternal parts, especially without necessity for complete breakdown ofall the mixer 10 parts to get at them, and even without taking the mixer10 out of the line, the mixer 19 according to the invention has verysuperior mixing and control of mixing characteristics. Indeed thecombination of these attributes, i.e., ease of access to working partstogether with excellent control of excellent mixing characteristics, isitself .a feature of the invention.

Mixing, of course, as is taught in the prior art, occurs because of thevibration of blade tip 91a in the high pressure jet formed from orifice100e, causing cavitation phenomena. It is desirable to vary the orifice1002 to blade tip 910 distance to maximize this phenomena with a givenfluid and upstream fluid pressure. The manipulation of micrometeradjustment means 50 accomplishes this variation of orifice to blade tipdistance. Similarly, it is desirable to vary the ambient pressure atblade tip 91a to affect the'cavitation phenomena. This occurs with thepresent invention because of varied back-pressure supplied by valve 23,80 downstream of tip 91a. Thus, adjustment of micrometer means 40adjusts the distance between valve member 80 and seat member 23, therebyadjusting the ambient pressure at blade tip 91a and tuning the mixing.

In operation, the mixer 10 is placed in a line by attachment to adaptors26, 27, and the fluid flow is commenced. An acoustic pickup 130 (FIG. 3)monitors the acoustic energy present at a point immediately upstream ofvalve seat member 23. Pickup 130 is attached to an acoustic meter (notshown) which indicates acoustic intensity. The micrometer adjustmentmeans 51 is then adjusted until the orifice 100e to blade tip 91adistance produces maximum acoustic intensity as indicated by the meter.This will of course vary with the fluid in question,

what if any load of solid particulate or liquid material it is carrying,etc. Once set, the micrometer 51 reading (on indices 56d and 560,FIG. 1) may be recorded, and a set screw 51x is tightened to lockthimble 51 in place on flange 21a so that the correct setting will bemaintained.

Then the micrometer adjustment means 40 will be manipulated until thevalve 80, 23 is tuned to the maximum cavitation effect as recorded onthe acoustic meter (not shown) attached to pick-off 130. Again, thiswill vary with the liquid in question, and operating conditions.Readjustment of micrometer adjustment means 50 may then be necessary,and another, finer adjustment of micrometer adjustment means 40. In anyevent, when the final adjustment of means 50 is made, the micrometerreading is taken and recorded as with means 40, and a set screw 41x isengaged to lock thimble 41 in place on flange 22a thus maintaining thecorrect setting.

Thus, it is yet another feature of the invention that fine adjustmentsof the blade tip 91a to orifice little distance, and the back pressurevalve can be made; that because of the micrometer aspect thereof theyare fully reproducible; and that they can be locked in place by screws51x,

1x so that the mixer can maintain its setting during operation.

Also, as has already been indicated, since the mixer 10 requires apressure head at the upstream inlet up to 800 psi, which often isapplied by a positive displacement pump, it is a safety feature of theinvention that full blockage is afforded by valve 80, 23 when seated asillustrated, but that under pressure overload this is vented by themovement of piston 83 against spring 84. This feature allows completeseating of valve member on seat member 23 within the range if axialmovement of valve member 84 because the corresponding high degree ofback pressure may be needed in a given tuning situation, i.e.,near-complete seating may be required. Thus it does not compriseoperating flexibility because of safety, but rather provides both. Theconical nature of the valve parts 80, 23 affords smooth application ofback pressure and contributes to the fine tuning thereof possible withthe invention, because the flow stream is disturbed symmetrically andsmoothly.

What has been described is a mixer 10, which is capable of very fine,reproducible, micrometer adjustment of internal parts to afford maximummixing intensity, yet which can have its working parts removed forcleaning and the like without taking down the whole assembly, or evendisconnecting from the line. These and the other features disclosedhereinabove afford a significant advance in this art.

The invention has been described with reference to an illustrativeembodiment thereof. Of course, variations therein are contemplated.Those skilled in the art will recognize many equivalent arrangements ofparts followmg the principles of the invention set forth and illustratedabove and claimed below.

What is claimed is:

1. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outletend thereof, and including a first pan of opposed lateral slots at afirst axial position, and a second pair of opposed lateral slots at asecond axial position, along said housing;

(b) a jet-forming orifice structure within said housing situatedupstream of said first pair of slots;

(c) a blade assembly carried within said housing with the blade edgethereof facing said jet-forming orifice;

(d) a first elongated axially slidable member carried on the outside ofsaid housing, normally covering said first pair of slots and includingremovable means connecting said blade assembly thereto through saidslots for axial movement therewith;

(e) a first micrometer movement removably engaged with said firstslidable member for precise and repeatable setting of the axial positionof said first slidable member and thereby said blade assembly;

(f) a valve assembly carried within said housing downstream of saidblade assembly, including a fixed portion and a movable portion;

(g) a second elongated axially slidable member carried 0n the outside ofsaid housing, normally covering said second pair of slots, and includingremovable means connecting said valve assembly movable portion theretothrough said slots for axial movement therewith; and

(h) a second micrometer movement removably engaged with said secondslidable member for precise and repeatable setting of the axial positionof said second slidable member and thereby of said valve assemblymovable portion.

2. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outletend thereof and including a pair of opposed lateral slots at an axialposition along said housing;

(b) a jet-forming orifice structure within said housing upstream of saidpair of slots;

(0) a blade assembly carried within said housing with the blade edgethereof facing said jet-forming orifice;

(d) a valve assembly carried within said housing downstream of saidblade assembly, including a fixed portion and a movable portion;

(e) an elongated axially slidable member carried on the outside of saidhousing, normally covering said pair of slots, and including removablemeans connecting said valve assembly movable portion thereto throughsaid slots for axial movement therewith; and

(f) a micrometer movement removably engaged with said slidable memberfor precise and repeatable setting of the axial position of saidslidable member and thereby of said valve assembly movable portion.

3. A tunable acoustic fluid mixer comprising:

(a) a housing providing a fluid passageway from an inlet to an outletend thereof, and including a pair of opposed lateral slots at an axialposition along said housing;

(b) a jet-forming orifice structure within said housing upstream of saidpart of slots;

(c) a blade assembly carried within said housing with the blade edgethereof facing said jet-forming orifice;

(d) an elongated axially slidable member carried on the outside of saidhousing, normally covering said pair of slots, and including removablemeans connecting said blade assembly thereto through said slots foraxial movement therewith; and

(e) a micrometer movement removably engaged with said slidable memberfor precise and repeatable setting of the axial position of saidslidable member and thereby of said blade assembly.

4. A mixer according to claim 3, wherein is further included, anadjustable valve assembly carried within said housing downstream of saidblade assembly.

5. A mixer according to claim 2 wherein said valve assembly fixedportion comprises a valve seat, and said movable portion comprises avalve member.

6. A mixer according to claim 2 wherein said valve assembly fixedportion comprises a valve seat, said movable portion comprises a valvemember located downstream of said valve seat, and said valve member isspring loaded in the upstream direction so that limited relief movementis afforded in the downstream direction under fluid pressure overloadsupstream thereof.

7. A mixer according to claim 1 wherein a third pair of opposed slotsare provided adjacent said jet-forming orifice structure, and a thirdslidable member is carried on the outside of said housing overlying saidthird pair of slots, to allow access to said orifice structure forremoval thereof.

8. A mixer according to claim 1 wherein said valve assembly fixedportion comprises a valve seat, said movable portion comprises a valvemember located downstream of said valve seat, and said valve member isspring loaded in the upstream direction so that limited relief movementis afforded in the downstream direction under fluid pressure overloadsupstream thereof.

9. A mixer according to claim 1 wherein each of said micrometermovements comprises a thimble having a threaded portion engaged with athreaded portion of the respective slidable member associated therewith,so that rotation of said thimble moves said associated slidable memberaxially.

10. A mixer according to claim 9 wherein each said thimble includes adisengageable retaining ring which limits the axial movement of theassociated slidable member, so that when said ring is disengaged theslidable member can be retracted axially away from the associatedthimble suflicient to expose the associated pair of slots in saidunderlying housing.

11. A mixer according to claim 9 wherein the thimble of each micrometermovement, and the associated slidable member, each bears indiciaallowing precise resetting of any relationship therebetween.

12. A mixer according to claim 1 wherein each micrometer movement islockable at any setting, so that any setting can be maintained duringoperation.

13. A mixer according to claim 2 wherein said valve assembly fixedportion comprises a conical valve seat, wherein said movable portioncomprises a conical valve member located downstream of said valve seatand Wherein said valve member is spring loaded in the upstream directionso that limited relief movement is afforded in the downstream directionunder fluid pressure overloads upstream thereof.

References Cited UNITED STATES PATENTS 3,169,013 2/1965 Jones 259-43,176,964 4/1965 Cottel et a1 2591 3,278,165 10/1966 Gaffney 259-1ROBERT W. JENKINS, Primary Examiner.

J. M. BELL, Assistant Examiner.

